I recall one of the women who signed a deposition for John Ray said that she and her boyfriend (an NYC cop) first met Rex, he and his wife were both members of the "swingers" club in Manhattan. When they attended a swinger party at Heuermann's house some time later, Asa was present and pregnant, so not participating. According to that woman, Asa knew of Rex's swinging with other couples and participated, too. If that statement is accurate, it means Asa knew of her husband's kinky sex habits with other women, so she had to know something was up in his basement room with the door locked.
Another woman sex worker who submitted a deposition for John Ray claimed that Rex took her to his home, to his basement room for sex and that his wife was at home at the time.